Step 4: The solar cooker.

Step 5: Testing testin testing!

I used this clock to do a demonstration once before but this is the first time I set it up to actually run a solar cooker. My test was run from about ...

The Sun's path across the sky has been known and has been predictable for a very long time. People with solar panels and solar cookers take either a high tech approach to solar tracking (light detecting electronics, etc or they manually adjust the cooker or panel. High tech is very expensive and manual adjustment is majorly error prone.
Low tech cheap tracking could improve solar performance substantially.
Low tech tracking would be valuable in really poor countrys for solar cooking and perhaps save many trees from the cooking fires.
This instructable describes my tracker that I made from an old and ugly clock.
This is a collaboration so if you have an old clock lieing around, please set it up with a gearwheel as I did and see how sturdy it is. If we can find a strong robust one, It could be bulk ordered for appropriate tech solar timing projects.
Brian

Step 1: Stripping the clock

First thing I had to do was to take the hands off the clock.
The hands are attached to 3 concentric shafts that are connected to the gear wheels in the clock
I had to find the wheels inside that turned the minute and second hand and cut off the pieces that went up through the middle. therefore I was left with the shaft that turns the hour hand. The hour hand is friction fit onto the shaft.
I wanted something stuck on much more firmly!

Unfortunately I dropped the clock during my taking it apart and I cracked the connection to its face.

You could also try a small motor out of an old microwave oven, they are used to spin the microwave generator 'scatter' plate as well as the food turntable. They have metal gears and spin at ~ 2-8 rpm. Just an idea, I have used them to create turntables to show off my motorcycle models. (Unfortunately, the pictures were on my old PC which suffered an untimely death.) Wonderful idea.

Excellent...thank you for posting your great tracking unit.... And to those who have been critical of Brian's work, the ' you need to do it this way' or why didn't you do this, add that....and so on.... Get to your drawing/design boards, spend the time, build a unit, take pictures, make a video, make drawings, diagrams and charts and write up step by step directions, with material lists.....then post it here for man kind to have at its perusal ....and be sure to ready to be bombarded with cynical criticism.....

Brian, that you for sharing your design, saving me hours & hours of R&D, it is refreshing, indeed, to have people like you, share their findings w/out expecting anything in return but those following having success .... And benefiting from their hard work....

I wish you health, happiness & prosperity....again, thank you for this post & look forward to more in the future

Richard, sie

Rancho El Starvo

Te Jas, on the Red River, half a mile south of Native America aka Oklahoma

Hi, thanks, it is not that great, I never did find a clock that was stronger. After that I went on to making drippers for gardening that would probably work better than the clock for rotating the lazy Susan.

https://www.flickr.com/photos/52815627@N06/8036249196/ The drip from that is very reliable, probably nearly as good as the clock and I have done it in 5 gallon bucket size too with dog dishes or aluminum dishes as the float. It is tough to get round to everything because my job takes a lot out of me. Anyway, if you do any new solar cooking stuff, I recommend the float and dripper as a better way of controlling a rotation. Brian

The Intermatic Timers used for sprinklers water heaters etc, have a pretty strong clock motor to trip the switch inside. But they come with their own problems, not exactly cheap or commonly thown away & they need 110 V (or depending on model 220 V ) to run.

I think it is unfair to call it a Rube Goldberg machine. The float and bucket of water act both as ballast and as protection against wind damage for the clock driver. If you want Rube Goldberg, try letting the water dripping out of it onto a vegetable patch! I made a 2 bucket version where the water drips out and raises a float in another bucket (instead of having a counterweight) but it was a pain to take the water out of the bottom bucket at the end of the day! (definitely a more poetic version though!) Simple trackers are needed in poor countries for solar cooking so I invite people to make their own and make better versions. Think of it as volunteer work in your back yard! Brian

I don't get where people are calling this an RG!RG used 'complex' ways to do simple thingsThis is simplicity doing something complexGeeshThank you Brian for your instrut, I like your idea of using 2 bucketsI was also thinking about trying one with an orifice to control the drip rate

No RG used simplistic ideas in a overly complex ways. There was no insult meant in say it was an RG. Perhaps we can get away from calling it an RG and call it a GT (gaiatechnician), meaning it's a new and different way of thinking.

I have a new diagram that is probably something that people would much prefer doing It is http://solardesign.ning.com/photo/liquid-piston-tracker If you have your solar panels on equatorial mount, I think the liquid piston device would be an ideal way of turning them. I also have a video about equatorial mount for solar panels which is probably the best out there right now! (because there are no others!). It is definitely worth a look before you start into a project. Brian

WOW! I'm calling it Rube Goldberg too, and saying that with the greatest respect. Even conceiving of such a machine is impressive. To then build it and make it work...well, my hat's off to ya, and I bet Mr. Goldberg's is too.

Well , I disagree. Rube Goldberg was about needless complexity. It is needless complexity to have a photo cell searching for the sun. Any astronomer who has a telescope with equatorial mount and a little electrical driver to follow the stars automatically can tell you that. All I was trying to do was use a clock as a very cheap mechanical timer. Clocks are so delicate that I could not use them to power anything. Really it is not very complicated at all.

I was speaking tongue in cheek. My real meaning was/is that you're thinking outside the box. In fact, throwing the box away. But I obviously didn't get that across. So more directly, whoa, very cool concept, very cool execution!

Sorry. On another site the Rube Goldberg aspect was clearly all that people saw. It sometimes feels like people are ganging up to quash the thought. Anyway, thanks for the encouragement. I do think it is simple but It took many months with the notion in the back of my mind to come up with it.

Yes, I am brian. I know the diagram is not much good. I made it before I thought of a "gearwheel" instead of an hour hand . Perhaps osomeone can try different kinds of electric clocks to find the best one for this type of project. They seem mostly the same to me but perhaps certain brands are better, more robust or cheaper? As soon as the green science fair is over,(8th June, just 4 days to make this a winner!) I will make this a collaboration. Hopefully people will give their input and the how-to will get really good. The potential is there to make millions of solar panels and solar cookers 20% better! Adapt a clock today!

cool... its does seem that your setup is essentially a rope style pump... If thats the case, isn't the rope suppose to go in a loop? Also... why does the clock has to be electronic, why can't you go for a standard physical pendulum with gravity powered weight. This would mean you will totally remove the need for the water ballast, as the the regulator would be stronger. This also reduces the number of strings to one.

The set up is not a rope style pump. The clock just controlls the height of the water in the bucket. This is valuable because it removes the direct link between the controller and the reflector. The wind is the problem. If you have a direct link, it must be very robust. A small gust of wind would tear apart the gears of a clock (perhaps this is why solar trackers are expensive?). The link is indirect, so the effects of gusts of wind are absorbed by the water in the bucket. I also made a 2 bucket version and that is a great buffer against the wind! A mechanical clock might be fine too. I cannot seem to find them anymore.

A re purposed grandfather clock? You can find them in some old antique shops, might be more expensive then your setup though. Or perhaps even a windup clock is better, since they are generally still robust. Modification would still be difficult. This is since they are usually metal.

About This Instructable

Bio:I am a stone mason. My hobby is making new solar cooking and gardening stuff. I have used solar heat to cook soil for a couple of years. In mother earth news in January, i read that their compost expe...read more »